European Union antitrust regulators charged Russian gas giant Gazprom on Wednesday with abusing its dominant position in Poland, Hungary and six other countries in Eastern Europe following more than two years of investigation.

The European Commission said the state-controlled company, a vital supplier of energy to Europe despite frequent political disputes, had hindered cross-border competition across the region and overcharged in five of the countries.

“We find that it (Gazprom) may have built artificial barriers preventing gas from flowing from certain Central Eastern European countries to others, hindering cross-border competition,” European Competition Commissioner Margrethe Vestager said in a statement.

“Keeping national gas markets separate also allowed Gazprom to charge prices that we at this stage consider to be unfair,” she said.

Her decision to move against Gazprom came more than two years after Brussels started investigating the gas group and just a week after she charged U.S. tech giant Google with abusing its market power after five years of hesitation by her predecessor.

Gazprom seek intergovernmental resolution

Russian gas giant Gazprom rejected antitrust charges and said it expected the case to be resolved by undertakings between the EU and the Russian government.

“Gazprom considers the objections put forward by the European Commission to be unfounded,” it said in a statement, insisting that its pricing and other policies were in line with legislation.

“Gazprom expects the resolution of this situation in the framework of agreement, previously reached between the government of the Russian Federation and the European Commission to find an acceptable solution to the antitrust investigation on the intergovernmental level.”